HRTEM investigation of phase stability in alumina�?�zirconia multilayer thin films

Bulletin of materials science

Chanchal Ghosh¹  E Mohandas¹  G Balakrishnan²  P Kuppusami³  Divakar Ramachandran¹ 

[1] Materials Synthesis and Structural Characterisation Division, Physical Metallurgy Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu, India$$Materials Synthesis and Structural Characterisation Division, Physical Metallurgy Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu, IndiaMaterials Synthesis and Structural Characterisation Division, Physical Metallurgy Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu, India$$;Department of Physics, PERI Institute of Technology, Chennai 600 048, Tamil Nadu, India$$Department of Physics, PERI Institute of Technology, Chennai 600 048, Tamil Nadu, IndiaDepartment of Physics, PERI Institute of Technology, Chennai 600 048, Tamil Nadu, India$$;Centre for Nanoscience and Nanotechnology, Sathyabama University, Chennai 600 119, Tamil Nadu, India$$Centre for Nanoscience and Nanotechnology, Sathyabama University, Chennai 600 119, Tamil Nadu, IndiaCentre for Nanoscience and Nanotechnology, Sathyabama University, Chennai 600 119, Tamil Nadu, India$$

关键词: Alumina+zirconia multilayers;    laser ablation;    high-resolution transmission electron microscopy;    phase stabilization;    amorphous zones.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

Phase stability of nanostructured thin films can be significantly different from the stability of the same materials in bulk form because of the increased contribution from surface and interface effects. Zirconia (ZrO₂), stabilized in tetragonal and cubic phases, is a technologically important material and is used for most high temperature applications. In literature, zirconia can be found to be stabilized in its high temperature phases down to room temperature via two routes, doping with divalent or trivalent cations and crystallite size controls. Apart from these, in the alumina/zirconia thin-film multilayer system, a constraining effect on the zirconia layers provides another route to stabilization of the tetragonal zirconia phase at room temperature. However, in such nanostructured geometries, at high temperatures, the small diffusion lengths involved can influence the phase stability. The present work deals with the high-resolution transmission electron microscope (HRTEM) studies of pulsed laser ablated aluminaâ€�?�zirconia thin-film multilayers in the as deposited state and annealed up to 1473 K at 2 Ã�? 10^âˆ�?5 mbar. Conventional techniques such as X-ray diffraction lack the ability to detect localized phase changes at nanometre length scales and also for the low volume fraction of newly formed phases. Cross-sectional HRTEM techniques have been successful in detecting and characterizing these interactions.

【 授权许可】

Unknown